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Minimum malted grain %


nabtastic

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Hey all,

I've been looking for a rule of thumb regarding the minimum percentage required for full starch conversion for each malted grain -

2-row malted barley (pilsner)

6-row malted barley (pilsner)

malted rye

malted corn

distiller's malted barley

So for example, say I desire a mash bill of (unmalted) corn & malted barley, for full conversion I would have to have on minimum x% 2-row, v 6-row, v distiller's.

I understand that the min % might change some off of the base grain, I'm just looking for a ballpark, 5/10/15/20% for each grain. A later discussion might include ideal conversion temps given that they each have different amylase compositions, but that's day 2 stuff.

Thanks

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It all depends on the conversion power of the enzymes of the malted barley. 2 row pilsen is only about 90 to 120 DP (Diastatic Power) Distillers malt is more like 270 to 300 DP.

Pilsen can only convert about 40% of the base malt, by weight, in adjuncts. Distillers malt has been used successfully down to 8% if rye is present (5 to 7%) to help with the liquefaction.

A lot of rye results in a slimy mess that is very difficult to distill because it fouls heat exchanges and steam jackets resulting in 20+ hour distilling days.

If you use unmalted corn, it needs a good cook before conversion. This is a minimum of 190F for 90 minutes. Some might say "Boil the piss out of it" which is a useless waste of energy. The highest gelatinization temperature for corn is 185F. Adding a lot of malt requires lowering the temperature of the cooked corn down to at least 160 to 165F. The grain will lower the mash the rest of the way. 150 to 152F results in more maltose and less maltodextrin (unfermentable). If you want real good conversions, liquid enzymes are your friends. They are cheap and very effective. Used at really small amounts, as low as 0.007% they contribute no flavor. The enzymes also relieve your equipment the burden of moving heavy viscous mash.

As far as malting corn is concerned it is rather easy. Steep in cold water for 3 days, changing the water every day. Place in a warm place 75F+ turning over every 12 hours until the green part is 2 inches long. Then it is fully modified. If you dry it at this point it can be saved a long time. If you grind it green it turns to the consistency of peanut butter.

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Thanks Sherman and fldme for the input. We've been talking about malting but don't have a way to process wet grains. I've heard talk of people using meat grinders for that though. I am familiar with the temperature requirements and the points at which particular enzymes are active, but from the brewing side, never really stretched the use of adjuncts to this point.

We've been using enzymes and have had good results but have been playing with malted barley as well. I've heard talk that grains, especially specialty grains (lower DP but still..) can come through quite strong in the final product..

I suppose I should reword the question - is there a formula (rough or exact) that determines the amount of diastic power needed to convert a given amount of grain?

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The thing with enzymes is that they aren't "alive," and they continue to do their work until denatured or taken out of their temperature comfort zone. So, theoretically, with enough agitation, you can saccharify your entire mash with a very small amount of malt. But most of us do this for a living, and we don't have all day to wait for our mash to convert.

Diastatic power is measured in degrees Lintner, and as a rule of thumb, your mash should not be below 90 L. If it is below 75, you will have very disappointing yields. There are plenty of diastatic calculators on the web, but even if you go through all the complicated math, it comes out pretty close to simply using an average with dry weights. For instance, if you have 50 lbs crystal malt with 0 L, and 50 lbs 2 row pale with a DP of 125 L, then your resulting mash will be (very close to) 62.5 L, which means your conversion rate will be pretty low. Hence the heavy reliance on base malts in brewing.

Now, bear in mind that most brewers don't agitate their malt (unless they're using a 4 vessel system with a mash mixer), and us distillers can often get away with amounts that are a bit lower. I've had success with rye and corn mashes with DP's below 70. Having said that, Sherman is on the money about commercial enzyme. The same mash at a DP of 70 L with a single cup of enzyme gave my mash yield a tremendous boost. I'm talking 25%+ here.

If you decide to go with malts for all your DP, make sure you count whatever modification that is present in your rye, corn, sorghum, millet...whatever. Then you can spec your barley malt bill using whatever you like for flavor Pilsner and and pale malts average around 100. Rye malt is around 105.2 row and Maris Otter types can be as high as 175, but average around 140-150. 6 rows vary, but Briess runs around 190. Distillers malt runs around 150. Also, wheat malts have rather high DP that are worth considering. I think soft red wheat malt is something like 200.

Hope that helps!

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Hey Nabtastic,

Like Sherman and Natrat have mentioned, the DP of the malt is very important when considering efficient conversion of the mash. General rules of thumb about enzyme activity...

Enzyme activity is a factor of:

1. Temperature

Higher temperatures increase enzyme activity to the point that the enzyme begins to die (denature).

2. pH

Landing within the optimum pH of the enzyme will increase its activity because it is more stable.

3. Agitation

The more the enzymes are moved around, the more they will "bump" into the substrate (starch) and convert it.

4. Concentration (of the enzymes vs. substrate [starch in this case])

Too much starch and not enough enzymes means the conversion will take longer.

The following link has a pretty nice chart about the various activity ranges of malted barley enzymes.

http://realbeer.com/jjpalmer/ch14.html

Cheers!

SpecZyme

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It all depends on the conversion power of the enzymes of the malted barley. 2 row pilsen is only about 90 to 120 DP (Diastatic Power) Distillers malt is more like 270 to 300 DP.

Pilsen can only convert about 40% of the base malt, by weight, in adjuncts. Distillers malt has been used successfully down to 8% if rye is present (5 to 7%) to help with the liquefaction.

A lot of rye results in a slimy mess that is very difficult to distill because it fouls heat exchanges and steam jackets resulting in 20+ hour distilling days.

If you use unmalted corn, it needs a good cook before conversion. This is a minimum of 190F for 90 minutes. Some might say "Boil the piss out of it" which is a useless waste of energy. The highest gelatinization temperature for corn is 185F. Adding a lot of malt requires lowering the temperature of the cooked corn down to at least 160 to 165F. The grain will lower the mash the rest of the way. 150 to 152F results in more maltose and less maltodextrin (unfermentable). If you want real good conversions, liquid enzymes are your friends. They are cheap and very effective. Used at really small amounts, as low as 0.007% they contribute no flavor. The enzymes also relieve your equipment the burden of moving heavy viscous mash.

As far as malting corn is concerned it is rather easy. Steep in cold water for 3 days, changing the water every day. Place in a warm place 75F+ turning over every 12 hours until the green part is 2 inches long. Then it is fully modified. If you dry it at this point it can be saved a long time. If you grind it green it turns to the consistency of peanut butter.

. How much more sugar are you getting out of corn by holding it at 190 for 90 minutes? I have tried it all kinds of ways, and if you take it up to 190 and hold it a few minutes, then drop it and add malt, I have not seen it add one bit more of sugar. Maybe I am missing something.
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Thanks guys,

We've been using enzymes and have had fairly good results so far. Our mash tank is less than ideal, but it's all that we have to work with now - so I'm making it work. We just got in some DM, Malted Red and Malted White wheats, and some pre-gel corn flakes. currently this is a very very hands on process for us (involving hours of manual stirring) so anything I can do to maximize yields is the priority at the moment. I found this little gem on Wiki, I'm thinking that this will come in handy in recipe development.

In Europe, diastatic activity is often stated in Windisch–Kolbach units (°WK). These are related approximately to °Lintner by:

34f13b5479ed3382057daf9aeb4ea117.png58dfc35cf6ae78932cc497d504ac21f1.png.

100.0 °Lintner equals 3.014 × 10−7katal or 18.08 enzyme units.

I can say for certain that our corn doesn't cook that high for that long, the average is more like 175 for 2 hours. That being said our efficiency is in the low 80's so not bad all things considered.

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. How much more sugar are you getting out of corn by holding it at 190 for 90 minutes? I have tried it all kinds of ways, and if you take it up to 190 and hold it a few minutes, then drop it and add malt, I have not seen it add one bit more of sugar. Maybe I am missing something.

IMHO, you don't have to hold it quite that long, but Sherman is being cautious, and when people brand new to mashing are asking questions, caution is frequently the best path.

I will say, though, that higher temperatures than 190 are warranted when you're using high nitrogen (low quality) adjuncts. You will indeed improve your yield by raising to boil or pressure cooking. Many here are mashing blind---- using grains from farms with no QC tests on the grains they are using. They have no idea what the starch contents are of the grains they use, let alone the nitrogen content.

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The reason for the seemingly long cook time at 190F is to overcome the hard to digest starches. The yield is improved by about 10 to 12% utilizing SEBStar HTL with the extended cooking time. The reason I don't go on up to boiling is to not denature the enzymes. It is a compromise of time vs energy. Generally, If I formulate a corn only mash for 17 BRIX I usually hit 17+.

During the 190F steep there is no energy input to the system. It is simply a matter of getting the mash to 190 and allowing it to sit. Most of the time the mashes of 300+ gallons have no issue holding the heat. I do also have to add that most of the time with 100% corn and enzyme mashing I am using greater than 2 lbs per gallon of mash. The SEBStar HTL eliminates any viscosity issues. Fermenting a 9 to 10% mash is normal with this regimen. A 6% mash without enzymes is physically difficult and hard on most craft equipment.

Sorry to go off subject but the questions lead to the answer.

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